Hope Ball is seen here with whale bones on a beach in Barrow, Alaska.
HOW DO WHALES get so fat? And could the answer have any bearing on human obesity?
Hope Ball, a graduate student in The University of Akron’s integrated biosciences program, set out to answer these questions by conducting the first study on leptin — the "fat hormone" — in whales.
Leptin tells the brain when to stop eating; evidently bowhead whales — the most blubbery creatures on the planet — are not getting the message.
"No one has looked at leptin in whales before," says Ball. "These animals [bowheads] live in the Arctic and require a lot of fat for insulation. The question is, do they make leptin, and how is it signaling?"
Answers may be found on Alaskan beach
To answer these questions, Ball traveled to Barrow, Alaska, to assist whale anatomist Dr. JGM "Hans" Thewissen, professor of anatomy at Northeast Ohio Medical University (NEOMED), in the collection of tissue and bone samples from seven bowhead whales.
Ball and Thewissen discovered that leptin performs the same regulatory functions in whales as it does in other mammals, including humans. Yet somehow whales maintain their extreme fatness despite the appetite-suppressing hormone.
"There is something happening in the brain that doesn't tell the animals to stop eating," adds Ball.
There may be something happening in the brains of obese humans, too, she says.
Dr. Joel Duff, a UA professor of biology, explains that studying leptin can help scientists better understand its role in human obesity.
Leptin studies will continue
"Now that we know whales make leptin that is similar to that of other mammals, it is important to know just how much leptin is made, as the changes in leptin production in fat cells has been shown to be correlated with changes in obesity levels in humans," he says.
Ball's findings were published in the Jan. 16, 2013, PLOS ONE online journal, in a paper titled "Leptin in Whales: Validation and Measurement of mRNA Expression by Absolute Quantitative Real-Time PCR." The paper is co-authored by Duff, Thewissen, Dr. Richard Londraville, a UA professor of biology, and UA graduate Robert Holmes.
Ball says she plans to continue her research on leptin in whales.
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Story by Nicholas Nussen
Media contact: Denise Henry, 330-972-6477 or henryd@uakron.edu.